CHICAGO -- Former Chicago Bears quarterback Jim McMahon frequently walks into a room and forgets why he's there. His memory is "pretty much gone," he says.
It stems from his 15 seasons in the NFL during a time when quarterbacks did not receive as much protection as they do in the league today.
"I'm going through some studies right now, and I am going to do a brain scan," McMahon told the Chicago Tribune. "It's unfortunate what the game does to you.
"I've worked with some neurosurgeons and it's a very serious thing, man."
McMahon, who helped the Bears win the Super Bowl in 1986, has decided to help raise awareness of brain trauma by hosting a fundraiser in Chicago, with the proceeds going to educational programs and clinics for area youth coaches.
The 51-year-old McMahon, who was an All-American QB at BYU, is working with the Sports Legacy Institute, which promotes the study, treatment and prevention of the effects of brain trauma in athletes.
"He's going to become very active and try to get as many former players involved as he can," Laurie Navon, McMahon's girlfriend, told ESPN.com on Wednesday.
"He feels it's important to get more information out there. He and others took the blows for the young kids today, and now the rules are changing after they took all the hits."
Navon said the physical toll from McMahon's playing career has affected his well-being.
"He definitely gets depressed, because he can't do what he used to do and wants to do," she said.